The invention relates to a construction and method for a frame slat of a heddle frame for a loom wherein a drive slot opening which receives a drive hook that reciprocates the heddle frame is reinforced.
The typical heddle frame includes a top frame slat and a bottom frame slat between which a number of heddles are carried in the frame. The bottom frame slat includes a connector block which is engaged by a drive hook of a drive mechanism to reciprocate the heddle frame in vertical motions during weaving. The connector block is carried in a hollow portion of the frame slat in the case of a tubular frame slat. For access to the connector, material has to be removed and a slot formed in a bottom wall of the bottom frame slat. This cutting and removal of material is in a critical area of the frame slat which is highly suceptible to fatigue by reason of the drive connection with the drive mechanism for the heddle frame. The removal of material weakens an already vulnerable area of the frame slat and numerous attempts have been made to reinforce this section of the bottom frame slat against structural fatigue and failure such as cracking.
In U.S. Pat. No. 4,254,802, a frame slat and method is disclosed wherein reinforcing plates are spot-welded to the frame slat in the area of the drive slot which is formed to receive the drive connector of the heddle frame drive mechanism. While this method is effective for reinforcing the drive slot area, it necessarily involves additional process steps in the constructing of the heddle frame which is both time and labor consuming. Additional weight is also added to the frame slat by this method.
With the increasing use of high speed looms in which the heddle frame is reciprocated in vertical motions at even faster rates, the weight and hence inertia of the heedle frame becomes critical.
Accordingly, an important object of the present invention is to provide a construction and method for a heddle frame wherein the drive slot formed in the bottom frame slat is reinforced in a simple and inexpensive manner without significantly increasing the weight of the frame slat.
Still another important object of the present invention is to provide a reinforced heddle frame slat and method which is reinforced without the need of additional reinforcing materials nor significant additional labor expense.